<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<script>
    function getSum(num1,num2) {
        var sum = 0;
        for (var i = num1;i <= num2;i++){
            sum = sum + i;
        }
        console.log(sum);
    }
    getSum(1,25);
</script>
<body>

</body>
</html>